The present invention is related to medical devices, methods and systems. More specifically, the invention is related to devices, methods and systems for accessing various blood vessels in a patient, such as one or both renal arteries and one or more peripheral vessels.
In the setting of interventional radiology, numerous conditions exist that warrant placement of various intravascular devices into the lower limb arteries (iliac, femoral, popliteal, etc.). Such devices may include catheters and guidewires for diagnostic purposes, or systems for therapeutic or prophylactic applications such as drug infusion, monitoring/sampling, angioplasty and stenting, possibly in conjunction with embolic protection. In any event, these procedures often involve the use of radiocontrast agents known to have detrimental effects on renal function.
In many instances, lower limb arteries intended for diagnosis or intervention are accessed via an “up-and-over” approach, which first involves gaining arterial access on one side of the patient, typically though not necessarily via a femoral artery. From that access point, one or more diagnostic, prophylactic, and/or treatment devices are advanced in a retrograde fashion through the iliac artery on the side of access to the aortic bifurcation and then down along the direction of blood flow on the contralateral side, through the contralateral iliac artery, into and possibly through the contralateral femoral artery, etc. to the site of treatment and/or diagnostic procedure. As mentioned above, performing the treatment and/or diagnostic procedure often involves injection of a radiocontrast agent to allow the physician(s) to visualize the treatment/diagnostic site.
The nephrotoxicity of radio contrast agents has been well established. In patients with known risk factors, radiocontrast nephropathy (RCN) is a prevalent adverse effect of interventional procedures utilizing organically bound iodine-based contrast imaging agents. While the full mechanism of RCN is not known, its detrimental results on morbidity and mortality are well documented, and it is hypothesized that local agent administration to the renal arteries during the time of contrast media exposure may mitigate the development of RCN. Agents in this case may include vasodilators, diuretics, or hyper-oxygenated blood or blood substitute. As well as agent infusion, the exchange of blood laden with contrast media and replacement of it with filtered blood, via use of an external blood filter/pump might be warranted.
Various apparatus and methods for providing local delivery of substances to renal arteries have be described by the inventors of the present invention in U.S. patent application Ser. No. 09/724,691 , filed Nov. 28, 2000; Ser. No. 10/422,624 , filed Apr. 23, 2003; Ser. No. 10/251,915 , filed Sep. 20, 2002; Ser. No. 10/636,359 , filed Aug. 6, 2003; and Ser. No. 10/636,801 , filed Aug. 6, 2003, the full disclosures of which are all incorporated herein by reference. Apparatus and methods for renal delivery of substances have also been described in PCT Patent Application Nos.: PCT/US03/029744 , filed Sep. 22, 2003; PCT/US03/29995 , filed Sep. 22, 2003; PCT/US03/29743 , filed Sep. 22, 2003; and PCTIUS03129585 , filed Sep. 22, 2003, the full disclosures of which are all incorporated herein by reference.
For the reasons described above, in some diagnostic and treatment procedures performed in the peripheral vasculature, especially in patients with renal risk factors, it may be desirable to concurrently provide for a means of renal protection via site-specific agent delivery to the renal arteries. Thus, a need exists for devices, methods and systems that provide access to one or more renal arteries and to one or more peripheral vessels. Ideally, such devices, methods and systems would allow for access and substance delivery through a common introducer device that provides access via a femoral artery. At least some of these objectives will be met by the present invention.